John T. Graves

John Thomas Graves (4 December 1806 – 29 March 1870) was an Irish jurist and mathematician. He was a friend of William Rowan Hamilton, and is credited both with inspiring Hamilton to discover the quaternions in October 1843 and then discovering their generalization the octonions himself (he called them octaves) later that same year. He was the brother of both the mathematician and bishop Charles Graves and the writer and clergyman Robert Perceval Graves. Life Born in Dublin 4 December 1806, he was son of John Crosbie Graves, barrister, grandnephew of Richard Graves, D.D., and cousin of Robert James Graves, M.D. He was sent to school in England, in the parish of Westbury-on-Trym, then a village outside Bristol, under the Rev. Samuel Feild (Field in the Oxford Dictionary of National Biography), later vicar of Hatherleigh. Feild has been described as a "prominent second generation evangelical Anglican"; he was one of two curates in the parish, under Richard Carrow, the parish priest, as perpetual curate. Graves was an undergraduate at Trinity College, Dublin, where he distinguished himself in both science and classics, and was a class-fellow and friend of William Rowan Hamilton, graduating B.A. in 1827. He then moved to Oxford, where he became an incorporated member of Oriel College, 11 November 1830. Graves proceeded M.A. at Oxford in 1831, and at Dublin in 1832. Having in 1830 entered the King's Inns, Dublin, Graves was called to the English bar in 1831, as a member of the Inner Temple. For a short time he went the Western circuit. In 1839 he was appointed professor of jurisprudence in London University College in a delayed succession to John Austin. Not long after, he was elected an examiner in laws in the University of London.